Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×
Mars Space

Mars Rover Breaks Free 195

QuantumFTL writes "According to an MSNBC story Opportunity, the same rover that scored an interplanetary hole-in-one, has broken free of an interplanetary sand trap. The MER science operations mailing list was abuzz this morning with the news, as soon as the first rear hazcam image indicating success came down. Engineers were praised for working long nights and weekends to make this extrication possible. Good job, NASA!"
This discussion has been archived. No new comments can be posted.

Mars Rover Breaks Free

Comments Filter:
  • How they did it (Score:2, Informative)

    by Anonymous Coward
    To simulate martian gravity, which is a third of Earth's, experimenters stripped one of the test rovers of two-thirds of its weight

    Soon, the Opportunity team was ready for action. On May 11, Pasadena commanded the rover to straighten its wheels. Two days later, Pasadena ordered those wheels to rotate 2.5 times, or about 80 inches.

    Since then, Opportunity has moved forward an average of 0.5% of the total distance that its wheels have rotated. That comes to 1.1 feet ahead out of 213 feet spun.
    • by zepmaid ( 694112 ) on Saturday June 04, 2005 @06:17PM (#12726030)
      Actually they played the Queen song "I want to break free" and the rover was like totally inspired to break free.
    • Re:How they did it (Score:5, Informative)

      by Alien Being ( 18488 ) * on Saturday June 04, 2005 @06:53PM (#12726192)
      "To simulate martian gravity, which is a third of Earth's, experimenters stripped one of the test rovers of two-thirds of its weight"

      That would reduce intertia too, making the simulator easier to move than the one on Mars. I wonder if a better simulation would have been to attach a helium balloon to the CG of the vehicle.
      • Re:How they did it (Score:3, Insightful)

        by spworley ( 121031 )
        The intertia (momentum) of the rover is effectively 0. It's moving at a speed of centimeters per day. A triple-mass rover would indeed have triple inertia, but 0*3 still equals 0.
    • by Peter Simpson ( 112887 ) on Saturday June 04, 2005 @07:16PM (#12726293)
      ...to remove a group of 3 martians with dust all over them, high-fiving each other :-)
  • by CrankyFool ( 680025 ) on Saturday June 04, 2005 @05:43PM (#12725829)
    I'm really not trying to be a troll here, but I'm wondering: What was the rush? Sure, this needed to get done, but why the need to work extra-long hours to do it? What would have happened if it took an extra month or two? (I read the article linked to with the text 'engineers were praised' and was not enlightened)
    • by eln ( 21727 ) on Saturday June 04, 2005 @05:49PM (#12725871)
      The Martians who were watching it all unfold were running out of popcorn and getting antsy. It would have been just a matter of time before one of them gave up and just kicked the thing.
      • The Martians who were watching it all unfold were running out of popcorn and getting antsy

        They really started getting worried when the Rover reported back "The Alien is nibbling on your arm...". At that point it was either have the engineers put in some long hours to find a solution or hit the space bar to release the cyanide gas...
      • So the rover snapped the chains holding it and swifty decked the guards, snatching their death ray pistols in the process. With the pistols firmly gripped in one pair of hands, the voluptuous rebel Martian princess, who was about to be sacrificed in cruel and barbaric ritual, gently nestled in the other, it proceeded deal out firey death to the supercilious Martians overlords, solving the problem of their incipient ennui quickly, if not so neatly. It had hair, it would be blonde and a lock would be rakis
    • by Sprotch ( 832431 ) on Saturday June 04, 2005 @05:50PM (#12725874)
      The rover is now long past its theoretical life span, any other part my fail, and that would be the end of it. One failure is hard to fix or work around, two is nearly impossible.
      • That depends on which part(s) fail. Loosing the radio(s) or solar panel(s) would be a disaster that cannot be worked around.

        Losing a drive motor might not be too big a deal - if there is one working on the other wheels. They just have to be more careful because less wheels would spin next time the terrain is touch. (I'm not sure how the rover is designed, but I would suspect that there is more than one motor, instead of a complex transmission, or 1 wheel drive)

        There are many lesser failures that can

        • (I'm not sure how the rover is designed, but I would suspect that there is more than one motor, instead of a complex transmission, or 1 wheel drive)

          Each wheel has an independent motor and the front and rear wheels each have their own steering motors. I don't know if the motors are powerful enough to drag a non-functional wheel.

      • The rover is now long past its theoretical life span

        Make that advertised life span. If it really was that much past it's theoretical life span, chances are it'd be long dead.
    • by mcb ( 5109 ) on Saturday June 04, 2005 @05:50PM (#12725876) Homepage
      Since Mars has a different length day than Earth (40 minutes longer), the engineers are sometimes working very odd hours (since the rover is only active during daylight on Mars).

      Aside from that I imagine they wanted to get it out as soon as possible since they have no idea how long its batteries will last, and it can't do any work while it's stuck. Perhaps they spent the off hours doing simulations and tests to figure out how to get it out.
    • well, considering they are already running the rovers in extra mission time, the sooner they got them free, the more time was left between getting free and the batery etc. giving their last bit of juice (and the rover dying).

      so if the batery would last another 6 months and they spend 3 months getting free, that's only 3 months left to explore.
      if they got free in 1 month however (by working overtime), then they would have 5 months to explore...
      if I had to choose, I would know what to pick :)

      btw, I think th
    • by Anonymous Coward on Saturday June 04, 2005 @05:52PM (#12725886)
      Rechargeable batteries cease to work. Solar panels get scratched and clogged by sand. Sand gets into the parts and joints. Did I mention this thing is basically sitting in a big pile of sand? Okay. Now did I mention that Mars, as a planet, is prone to really nasty windstorms?

      Every second that passes is one second closer to the point at which this rover simply ceases to function. Until that point comes, we want to get absolutely as much use out of it as possible.
    • Some of us can not stop trying to solve a problem once started. There are still those that live to work and find a 24hr day and long weeks to be a joy when it pays off. The guys and gals doing the rover work seem to be of this type. They are the real heroes of our time....they make the suits and pols look like the fakers they really are. 24hr days are good for the soul.
    • It's only designed to work for X number of days. After that it might fall apart and they know it.

      Mars has huge dust storms, it's freezing cold, the solar panels are getting scoured by the elements etc. If they don't get it out now, they might not get a second chance.
      • It's only designed to work for X number of days. After that it might fall apart and they know it.

        X = 90 sols (Mars days, which is a fraction longer than an Earth day). That was the intended lifetime of the rovers. The other rover, Spirit, just passed 500 sols.

    • by v1 ( 525388 ) on Saturday June 04, 2005 @06:08PM (#12725979) Homepage Journal
      Every day the rovers are sitting on Mars their solar panels are degrading, getting covered with dust, parts are being caked with sand and grit, radioactive materials used to keep bearing grease soft are decaying, battery capacity is dropping. They have a very limited lifespan, but thanks to Nasa's over-engineering in the extreme, they are both still functional, long beyond their minimum expected lifespan.

      For how long is anyone's guess. The rovers may only have a month of time left to live. Who knows what's just over the next dune to check out. To waste the rover's last hours just because a few people will have to work a little O.T. is, well... wasting a valuable Opportunity.
      • "Every day the rovers are sitting on Mars their solar panels are degrading"

        Didn't they find out that the solar windstorms blow the sand off of them and keep them clean?

        "radioactive materials used to keep bearing grease soft are decaying"
        iirc they're using radium 226 which has a half life of about 1590 years.

        I understand the point of your post, but these points for why it will fail are probably two unlikley points of failure.
        • Not just unlikely, but actually positive factors that could extend the life of the Rovers.

          Since they are already operating way past expected lifetime, they could actually make it for years.

          Even odds that a Rover is still functional when Longhorn comes out.

        • Cassini carried roughly 72 pounds of plutonium in generators needed to power the giant probe on its voyage to Saturn, where it will arrive July 2004. Each rover will carry an ounce of the radioactive element in eight penny-sized pellets to keep them warm during the Martian nights, which can reach minus 157 degrees Fahrenheit. They will also carry even smaller amounts of the radioactive elements, cobalt-57 and curium-244, to calibrate two science instruments.

          Source: www.nuclearpolicy.org/NewsArticle.cfm?Ne
          • Here's the half lifes you wanted to know:
            CO57 (cobalt-57) is approximately nine months (272 days)

            CM244 (Curium-244) is about 18.11 years

            It doesn't take a physics expert, in fact I'm simply a high school graduate (as of June 1 to boot)

            I think they'll last even after the radioactive elements decay. But you might just be right!
      • So, when your college roommates found a full keg of beer in the hall from last night's party, did you say, "Bah! This only means that sooner or later you'll be out of beer."
    • by AndroidCat ( 229562 ) on Saturday June 04, 2005 @06:09PM (#12725981) Homepage
      They should have just dropped another rover at the edge of the sandtrap and carried on. It would have cost them a stroke, but that's not so bad.
    • As others have already noted, the rovers are operating well past their mission time and could fail at any minute. There is an unknown quantity of time left to have the rover do whatever science it can.

      Also, it costs a great deal of money to keep a mission like this going. The longer the rover is playing in the sand without doing anything of value, the more money is wasted. NASA's budget is thin enough as it is. I guess they could always abandon that particular rover, but I don't think anyone wants tha
    • Because they want to get as much science done as long as the rover is operational.

      As it is, they're operating on 'free' time; the rovers were only expected to be at full operational capacity for 90 days...
  • by Junior J. Junior III ( 192702 ) on Saturday June 04, 2005 @05:43PM (#12725830) Homepage
    Now I'll know who to call next time my car gets stuck in the snow this winter.
    • Why don't you RTFA first? Then you'd realize that the stuck rover is nothing like a car being stuck in the snow. They had to do things completely differently.
      • True, but you could do the same with a car if you were stuck. (though if you were stuck worse it might not work) However most people are not willing to spend a couple months getting unstuck, so they use other methods. Then too, most people have abilities that the rovers don't have.

    • Now I'll know who to call next time my car gets stuck in the snow this winter.

      Good luck, but keep the following in mind before calling this guys:
      4 hours after your call you'll be called back an instructed to turn 30
      4 hours later you'll be instructed to drive back slowy for 1.5 minutes
      [...]

      I'd rather wait for Mister Plow instead...
    • No way. They'll just get started and then they'll get all excited because they've dicovered water on the surface. You'll never any work out of them after that.
    • Now I'll know who to call next time my car gets stuck in the snow this winter.


      Uh, winter will be over by the time these guys get you out and you'll owe about $12,000,000.



      c.

  • Cool! (Score:4, Insightful)

    by csharp_wannabe ( 886975 ) on Saturday June 04, 2005 @05:43PM (#12725831)
    To think...being able to wiggle out a remote control vehicle with no one near it...all I can say is Wow!
  • and was last seen heading for the border.
  • if it gets stuck back in the sand tomorrow? It sorta would, in that schadenfreude way.

    Anyway, I hope it doesn't, and props to the team for not giving up on it.
  • Reverse! (Score:5, Insightful)

    by Ford Prefect ( 8777 ) on Saturday June 04, 2005 @05:46PM (#12725852) Homepage
    I bet there's some scientists who'll be wanting the rover to reverse back a bit - it looks like they've dug the deepest trench yet on Mars, and I wouldn't be surprised if they've already done risk assesments regarding getting the rover to peer in with its instruments... ;-)
    • Re:Reverse! (Score:3, Informative)

      by Anonymous Coward
      Well, they certainly think about it:

      So what comes next? The first thing we're going to do is simply take a very hard look at the stuff we were stuck in. Much of the worst terrain was under the belly of the rover through all of this, down where we couldn't see it. From our new position, everything that was under us for all those weeks is now visible. So we're going to take a little while just to look at where we were. We may also turn to take a look at our tracks (or trenches, or whatever you want to call
  • by PxM ( 855264 ) on Saturday June 04, 2005 @05:46PM (#12725853)
    is that they were so busy looking at the rear hazcam that they didn't see the giant water trap right in front of them.
  • It's such a trooper!

    Rove little rover, rove like the wind!

  • Lifespan (Score:2, Redundant)

    by PxM ( 855264 )
    The rovers were supposed to run for 90 days, but they have been running for over almost 18 months. No one is sure when they're going to break down from dust and other long term problems, so it's a good idea to get as much info out of them as possible.
  • by scovetta ( 632629 ) on Saturday June 04, 2005 @05:56PM (#12725907) Homepage
    What I can't understand is, why didn't "management" come in and screw this all up? How could something that was supposed to last only for 90 days last for 18 months? Seems like with most things, if they are supposed to last for 90 days, they MIGHT make it to 93 or 94 days.

    My hats off to the engineers. I wish I worked at a place like that.
    • What I can't understand is, why didn't "management" come in and screw this all up?

      Considering that the last screw up of a Mars probe involves not converting measurements correctly [jamesoberg.com], "management" had a lot of incentive not to screw up this time around.
    • by grozzie2 ( 698656 ) on Saturday June 04, 2005 @07:25PM (#12726348)
      You dont understand the concept. The original 90 day estimate of lifetime was solely to keep the total mission budget down to a point it would be 'acceptable'. If they had actually added another 18 months of operations to the original budget, the project never would have got off the ground. Enter some 'creative engineering'.

      Start by factoring a worst case scenario for all the components on the rover, and come up with an expected mission time of 180 days (assuming a successful landing). Sprinkle in a safety factor of 2, and you have a 'design mission' of 90 days. Plan all budgets going forward with a '90 days on planet' segment for the mission, keeping budget numbers as small as possible, ie easier to get approved, and the likelihood of a 'successful mission' as high as possible.

      After a successful landing, and the rovers run around for most of the 90 days, you come to the 'amazing' conclusion that they are still going strong, and could well do so for a long time yet. Re-do all mission life calculations, but, factor in some best case scenarios for component life, rather than worst case, and remove you fudge factor of 2, and voila, you come to the conclusion rovers can easily go another year, maybe longer. Now you go back to the budget folks, and present it as 'ok, we spent 150 million getting these things onto mars, we only need another 10 million to run them for another year after a hugely successful primary mission'.

      From a budget point of view, it becomes a no brainer, for a mere 10 million more, you can triple or quadruple the science value of the original 150 million investment, whereas the whole project could well have been scrapped if the 10 million more was factored in from the get go.

      Management played the game exceptionally well on this one, they back end loaded the budget with 'extras' that end up impossible to be declined after the rovers actually ended up on planet, and survived the first 90 days of 'primary mission'. They knew this was the plan already prior to launch, but, by back end loading the budget, they kept the initial approval numbers a lot smaller (easier), and left the long running mission plans to be bonus, ie only presented up the food chain after the rovers survived the first 90 days, and then validated the 'real scenarios' for actual expected mission life.

      The real problem they have now, rovers are going strong even after the real planned life, and now they are in an ongoing game of keeping budget topped up. From this point forward, it's still going to be a no brainer though, with all the space hype focussing on mars talk, topping the budget for the rovers is the cheapest publicity that can be bought today, and it'll continue to help deflect criticism away from _other programs_ that soak up billions, and possibly even help justify the sacrifice of those programs since mars is now the focus of all the forward looking hype.

      There are some politicians that are hoping and dreaming the 2 rovers can go for another year plus, because, it'll give them a wonderful chance to do some funds diversions. You can bet your last dollar that there are plans afoot in washington to divert more funds to the rover operations, and use that as the excuse to claim not enough funding left to service hubble. It'll be a political coup, but it'll only work if the rovers are still roaming mars when hubble service mission gets to a 'now or never' state.

      • Everything up to the last paragraph made perfect sense...but the last paragraph blew it.

        Guy, Hubble is a dead scope walking. We won't be fixing it, ever. The rovers are doing interesting science, and they've captured the nation's interest...without taking pretty picture along the way. Let's figure out how to get things out of that.
        • Guy, Hubble is a dead scope walking. We won't be fixing it, ever.

          Of course, if the scope had been designed for automated servicing, then it would have a long future ahead of it.

          Alas, it was designed to help justify the shuttle, and as a result it will die with the shuttle - as originally intended. The planners didn't think the shuttle would get canceled anyway and that they'd lose the hubble as result. The hubble was intended to help prevent the shuttle from being canceled in the first place.

          Kind of l
      • Nice theory, but I gather that the effect of the dust devils cleaning the solar panels was a surprise to most people. The feeling was the sand and static would reduce the power output fairly quickly.

        On the other hand, I agree that the back end mission costs are negligable compared to the cost and risk of getting there in the first place.

    • by ScottMaxwell ( 108831 ) on Saturday June 04, 2005 @10:37PM (#12727137) Homepage
      What I can't understand is, why didn't "management" come in and screw this all up?

      :-) Well, as an engineer, I'm the natural enemy of management, so it pains me to admit this. But honestly, the management for this mission has been simply exceptional, and that's a largely uncredited reason for our success.

      Remember the Spirit Anomaly, where we lost contact for a while, a couple of weeks after landing? For all we knew at the time, we'd lost the rover. Pete Theisinger and Richard Cook, who were then the project manager and deputy project manager, went down to the press conference alone, so that (a) the engineering team could work on the damn problem without being distracted by the press, and (b) only their faces were associated with the problem. When things were going well, they brought engineers and scientists to the press conference (and let them do most of the talking). When things went wrong, they took the heat.

      The tradition continues with our current project manager, Jim Erickson. To take a recent example, Jim went down to the testbed to help shovel the dirt for the special "sandbox" we had to set up to figure out how to extract ourselves from this dune. (Jim's the guy squatting on the far left of this image [nasa.gov]. That wasn't one of the days he was digging.)

      They couldn't have done it without us. But I have to say, we couldn't have done it without them, either.

  • by halftrack ( 454203 ) <jonkje@gmailCOBOL.com minus language> on Saturday June 04, 2005 @06:00PM (#12725930) Homepage
    Why have we been wasting time with rockets when there's a (semi solid) interplanetary sandtrap we could travel on. Not to mention that it can not be that far when they managed to hit a golfball over it in one shot. Afterall the summary said that they scored an interplanetary hole-in-one.
  • YEE HAH! (Score:4, Funny)

    by varebel ( 133951 ) on Saturday June 04, 2005 @06:01PM (#12725937)
    If there was any question about Earthlings being the rednecks of the universe, that image of us rootin' up the martian surface oughta clear it up.

    Lock the hubs and put 'er in low lock. YEE HAH!!
  • by Saeger ( 456549 ) <farrellj@nOSPam.gmail.com> on Saturday June 04, 2005 @06:11PM (#12725998) Homepage
    ...the rover stopped to take a neat picture [exploratorium.edu] after it freed itself from the rut, only to get stuck once again in so doing!

    Everybody knows that in situations like that you're supposed to KEEP MOVING for a long ways after freeing yourself so that you don't sink back into similar muck nearby, but those nerds apparently missed that life lesson. :)

  • Golf (Score:3, Funny)

    by iamdrscience ( 541136 ) on Saturday June 04, 2005 @06:15PM (#12726018) Homepage
    the same rover that scored an interplanetary hole-in-one, has broken free of an interplanetary sand trap.
    Good thing all the water hazards are frozen then, isn't it.
  • Basically, they gave up trying to think their way out of the muck and just floored the accellerator and kept it down - 212 feet of wheel spin. So, are they are stuck in the next dune yet?
    • ...just floored the accellerator and kept it down...

      What else they could do? There aren't too many options. They couldn't rock it back and forth like a car, so all they could do was floor it. I don't really understand why they had to think about it for so long - it's not like there were any other options.
      • The problem of course is that it could dig in until it lay flat on its belly, after which it would not go anywhere again, so they had to confirm that the muck wasn't too deep, before they could put the pedal to the metal. I'm just wondering what will happen at the next little dirt heap, which is probably all of two feet further away.
  • NASA's Opportunity rover has broken free from the Martian sand dune where it had been stuck for more than a month,

    Now that's a whole lotta floorin'
  • by QuantumFTL ( 197300 ) * on Saturday June 04, 2005 @07:47PM (#12726471)
    There's some good discussion about this going on in #space at irc.freenode.org, I'd recommend it to anyone who is interested in the topic. Also we've been talking about software issues affecting the rover (if we get to sol 1000, just about every piece of ground software will be inoperable). It's a cool place, check it out.

    Cheers,
    Justin Wick

    P.S. First accepted story! w00t!
    • (if we get to sol 1000, just about every piece of ground software will be inoperable)


      Hm, why is that? Will their system clock roll over?

      • by QuantumFTL ( 197300 ) * on Saturday June 04, 2005 @09:35PM (#12726896)
        (if we get to sol 1000, just about every piece of ground software will be inoperable)

        Hm, why is that? Will their system clock roll over?

        Well, most of the software developed at JPL for the mission uses three digits to encode the sol number. Once we are past 999, this software, as written, will cease to function properly. This is something that can be fixed, but I believe it would take a lot of effort. It will be a miracle if we need to do that, but it's possible one of the rovers will still be marginally operational at that point.
        • I'm trademarking SOL1K, SYK, and obtaining sol1k.com right now. So layoff!
  • They have weekends on Mars? Bush can send us to Mars, but we've still got to do honeydo's on weekends? What's the use of being a geek?
  • by HalfWalker ( 113611 ) on Saturday June 04, 2005 @09:04PM (#12726785)
    Hey -

    On the Nasa Home Movies page, there is a very nice photo montage called

    "Rover Team Album" 2:49 at 11meg

    It has some very cool electronica music to go with it. I've been searching, but can't find any indication as to exactly what the music is.

    Anyone have any ideas ?

    You can get to it from here :

    http://www.nasa.gov/vision/universe/solarsystem/me r_main.html [nasa.gov]

    Select the "One Year on Mars" (View Flash Feature) link at the right, then choose "Home Movies" from the set of image links in the popup window.
  • If you look closely at the picture in the first link, you can see what appear to be tracks.. perhaps some sort of Martian tank? I can't believe nobody at NASA noticed those.. or maybe they're just hoping we won't notice.

    The other obvious answer is that they're faking the whole thing. Obviously there can't be tire tracks on Mars.. that picture was taken on Earth!

Do you suffer painful hallucination? -- Don Juan, cited by Carlos Casteneda

Working...